JPS6016630B2 - electrophotographic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic device, and more particularly to a recording device such as a copying device, a hard copy device, a computer output device, etc. that uses electrophotography.

Conventionally, in an electrophotographic method, a photosensitive plate and an electrostatic latent image holding medium such as an insulator are overlapped, and charges are transferred from the photosensitive plate to the electrostatic latent image holding medium according to optical information to form an electrostatic latent image. When separating the photosensitive plate and the electrostatic latent image holding medium after forming the electrostatic layer, if the electrodes between the photosensitive plate and the electrostatic latent image holding medium are open, the voltage between the photosensitive plate and the electrostatic latent image holding medium will increase. The temperature rose to a high level and discharge occurred, causing some of the transferred charges to escape and blurring of the image.

This causes a decrease in the efficiency of forming a static latent image and a decrease in image quality. In order to reduce this discharge, it is known to short-circuit the electrodes between the photoreceptor and the electrostatic latent image holding medium, but if the conductivity of the photoreceptor is low, this becomes almost the same as an open state, and discharge occurs. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional drawbacks and provide an electrophotographic apparatus with good image quality.

According to the present invention, a photoreceptor, an electrostatic latent image holding medium, an optical information irradiation means, and a voltage application means are provided, and the photoreceptor and the electrostatic latent image holding medium are overlapped, and the optical information irradiation means In an electrophotographic apparatus that forms an electrostatic latent image by applying a voltage by the voltage applying means while irradiating optical information onto the photoreceptor, after the static latent image is formed, while irradiating the entire surface of the photoreceptor with reference light. The electrode of the photoreceptor and the electrode of the electrostatic latent image holding medium are short-circuited or connected with a predetermined resistance to separate the photoreceptor and the electrostatic latent image holding medium, thereby reducing discharge at the time of separation. An electrophotographic device is obtained.

This will be explained in detail below using the drawings.

The figure is a schematic diagram for explaining one embodiment of the present invention.

In the figure, an electrostatic latent image holding medium 1 made of, for example, electrostatic recording paper, an insulator such as polyethylene terephthalate or Teflon, or a material on which a metal coating layer is attached to the insulator;
A substrate 2 made of glass or the like with an electrode 3 made of Nesa, metal vapor deposition, etc.
A photoreceptor 5 is laminated with a photoconductor layer 4 made of Se, CdS, CdSe, an organic semiconductor, etc., and a back electrode 7 made of conductive rubber or rubber or sponge with a conductive layer formed on the surface is attached to the substrate 6. A power supply 11 for applying a voltage between the pressing plate 8, the optical information irradiation means 10 such as a slide or a CRT (cathode ray tube), the electrode 3 of the photoreceptor 5 and the back electrode 7, and the static It is composed of rollers 12, 13, 14, and 16 for transferring the electrolatent image holding medium 1, a developing means 17, a fixing means, and a reference light irradiating means 19. Here, as an electrostatic image holding medium, electrostatic recording paper in which the surface of a conductive-treated base paper is coated with a transparent material will be used. As shown in the figure, a roll of electrostatic recording paper is sent between a photoreceptor 5 and a pressing plate 8 by a transfer roller 12, and when the feeding is completed, it is pressed against the photoreceptor 5 by the pressing plate 8. In this state, optical information is irradiated onto the photosensitive plate from an optical information irradiation means 101 such as a slide or a CRT, and a pulse voltage is applied from the power source 11 to form an electrostatic latent image on the surface of the electrostatic recording paper. Next, when the pressing plate 8 is released and the electrostatic recording paper 1 is separated from the photoreceptor 5, the photoreceptor 5 is irradiated with light by the reference light irradiation means 19 consisting of one or more light sources to apply photocarriers to the photoconductor layer 4. The conductive layer of the electrostatic recording paper and the electrode 3 of the photoreceptor are separated while being short-circuited or connected by a predetermined resistance. The voltage generated in the gap between the two can be minimized. As a result, it is possible to reduce discharge development in the gap, thereby reducing the charge of the static latent image and the blurring of the image. In order to connect the conductive layer of the electrostatic recording paper and the electrode 3 of the photoreceptor, for example, an electrode of a pressing plate or a feed roller 12,1 may be used.
This can be easily realized by grounding the conductive layer of the electrostatic recording paper by making 3 a conductor and grounding it, and using a power source 11 with low output impedance at OV as the power source 11. The electrode 3 of the photoreceptor may be grounded at the time of separation using a switch or the like. After a high-quality electrostatic latent image is formed in this manner, the electrostatic recording paper is fed and fed out as is, or is cut into a predetermined length by a cutter 15 or the like. Then, a toner image is created by a developing means 17 such as a liquid developer, a magnetic brush, a magnet dry, or a cascade developing method, and is fixed on the electrostatic recording paper 1 by a fixing means 18 such as an infrared lamp, a heater, a heat roller, a pressure roller, etc. You can get a hard copy. In the figure, a new light source 29 is shown as the reference light irradiation means, but for example, the optical information irradiation means 1
When a CRT is used as the light source, the light obtained from the entire screen of the CRT can be used as the reference light by illuminating the entire screen of the CRT.

Furthermore, when separating the photoreceptor from the electrostatic recording paper, the optical information irradiation means 10 is used as a means for irradiating the reference light onto the photoreceptor, and by irradiating the same optical information as that irradiated when forming the electrostatic port group. There may be. This is because the electric charge of the static lightning latent image decreases due to discharge when it is separated, but the part where the discharge occurs is the part where the static lightning latent image has a lot of charge, that is, the part that was irradiated with light when the static lightning latent image was formed. be. Therefore, by irradiating the same optical information at the time of separation, it is possible to increase the conductivity of the photoconductor layer located in the area where the latent image has a lot of charge, and it is possible to reduce the discharge at the time of separation. Although the electrostatic recording paper was used as the electrostatic latent image holding medium 1 in the above description, the same effect can be obtained even if other insulating films or the like are used.
Further, the electrostatic image holding medium 1 may be not only in the form of a roll but also in the form of a sheet or an endless belt. The present invention also applies when a photoconductor having a multilayer structure in which other photoconductors, resistors, insulators, etc. are laminated on the surface of the photoconductor layer of the photoconductor 5 shown in the above embodiment is used as the photoconductor. A similar effect can be obtained. As described above, according to the present invention, it is possible to reduce the discharge when the photoreceptor and the electrostatic latent image holding medium are separated, thereby obtaining an efficient electrostatic latent image with good image quality.

[Brief explanation of the drawing]

The figure is a schematic diagram for explaining an embodiment of an electrophotographic apparatus according to the present invention.

Claims (1)

[Claims] 1. A photoconductor, an electrostatic latent image holding medium, an optical information irradiation means, and a voltage application means, the photoconductor and the electrostatic latent image holding medium are overlapped, and the optical information irradiation means causes the photoconductor to be In an electrophotographic apparatus in which an electrostatic latent image is formed by applying a voltage by the voltage applying means while irradiating optical information to Electrophotography, characterized in that the electrode of the photoreceptor and the electrode of the electrostatic latent image holding medium are short-circuited or connected with a predetermined resistance to separate the photoreceptor and the electrostatic latent image holding medium. Device.